Detergent compositions

ABSTRACT

THERE ARE DISCLOSED HEREIN DETERGENT COMPOSITIONS CONTAINING A WATER-SOLUBLE ORGANIC DETERGENT COMPOUND AND AS A BUILDER THEREFOR THE NORMAL ALKALI METAL, AMMONIUM OR ALKANOL AMINE SALTS OF CARBOXYMETHYLOXYSUCCINIC ACID.

United States Patent Oflice Patented Sept. 19, 1972 U.S. Cl. 25289 5 Claims ABSTRACT OF THE DISCLOSURE There are disclosed herein detergent compositions containing a water-soluble organic detergent compound and as a builder therefor the normal alkali metal, ammonium or alkanol amine salts of carboxymethyloxysuccinic acid.

This application is a continuation-in-part of application Ser. No. 879,627, filed Nov. 24, 1969, and issued as US. Pat. No. 3,635,830, which in turn is a continuation-in-part of application Ser. No. 731,700, filed May 24, 1968, and now abandoned.

The present invention relates to detergent compositions containing a novel builder therefor.

BACKGROUND Eutrophication is the process of excessive fertilization of aquatic plants through enrichment of waters with nutrients, such as carbon, nitrogen, phosphorus, potassium, iron, trace metals and vitamins. Factors in the eutrophication of lakes, streams and estuaries are natural runoif, agricultural drainage, groundwater, precipitation, sewage and waste efiluents.

Although there is no present adequate proof, it has been postulated that the phosphorus-containing builders present in detergent compositions can be a factor in entrophication. Therefore any substitutes which do not contain phosphorus may decrease to some extent the eutrophication.

It is, therefore, an object of the present invention to provide detergent compositions with a builder compound which is free of phosphorus.

The compositions of the invention necessarily include both a synthetic builder and a water-soluble organic detergent compound. Such detergent compounds that are useful in the present invention are the anionic (soap and nonsoap), noniouic, zwitterionic and ampholytic compounds. The chemical nature of these detergent compounds is not an essential feature of the present invention. Moreover, such detergent compounds are well known to those skilled in the detergent art and the patent and printed literature are replete with disclosures of such compounds. Typical of such literature are Surface Active Agents by Schwartz and Perry and Surface Active Agents and Detergents by Schwartz, Perry and Berch, the disclosures of which are incorporated by reference herein.

The phosphorus-free builders for the detergent compositions of the invention are the normal alkali metal, ammonium and lower mono-, diand trialkanolamine salts of ether polycarboxylic acids selected from the group consisting of oxydisuccinic acid and carboxymethyloxysuccinic acid. The oxydisuccinic acid is also known as 2,2'-oxydisuccinic acid.

The builder salts of the ether polycarboxylic acids of the present invention can be generally represented as follows:

wherein R is H or CH COOM and M is selected from the group consisting of alkali metal, ammonium and substituted ammonium cations such as morpholinium, alkyl ammonium and mono-, diand trialkanol ammonium.

Typical of such materials are trisodium carboxymethyloxysuccinate, tripotassium carboxymethyloxysuccinate, trilithium carboxymethyloxysuccinate, triammonium, carboxymethyloxysuccinate, the normal monoethanolamine salt of carboxymethyloxysuccinic acid, the normal diethanolamine salt of carboxymethyloxysuccinic acid, the normal triethanolamine salt of carboxymethyloxysuccinic acid, the normal tetramethylammonium salt of carboxymethyloxysuccinic acid, tri(ethylammonium) carboxymethyloxysuccinate, the normal monoisopropanolamine salt of carboxymethyloxysuccinic acid, the normal diisopropanolamine salt of carboxymethyloxysuccinic acid, monosodium dipotassium carboxymethyloxysuccinate, disodium monopotassium carboxymethyloxysuccinate, the normal morpholine salt of carboxymethyloxysuccinic acid, and the like.

The weight ratio of carboxymethyloxysuccinate builders to detergent compound when used in laundering and hand dishwashing compositions, ranges generally from about 1:20 to about 20:1. When the novel builders are used in mechanical dishwashing compositions, the ratio of builder to detergent compound is from about 10:1 to about 50:1.

The carboxymethyloxysuccinate builders can be used either as the sole builder or where desired can be used in conjunction with other well-known builders, examples of which include oxydisuccinate tetrasodium and tetrapotassium pyrophosphate, pentasodium and pentapotassium tripolyphosphate, trisodium and tripotassium nitrilotriacetate, polyacrylates, starch or cellulose derived polycarboxylates, and the like. Other materials which may be present in the detergent compositions of the invention are those conventionally present therein. Typical examples thereof include the well-known soil suspending agents, hydrotropes, corrosion inhibitors, dyes, perfumes, fillers, optical brighteners, enzymes, suds boosters, suds depressants, germicides, anti-tarnishing agents, cationic detergents, softeners, chlorine releasing agents, buffers and the like. The balance of the detergent compositions is water.

The detergent compositions of the present invention may be in any of the usual physical forms for such compositions, such as powders, beads, flakes, bars, tablets,

to about 11. Therefore, the presence of a buffer in the detergent composition is usually desirable. Examples of such buffers are sodium silicate, carbonate or bicarbonate.

When the pH value of the wash solution is below about 8.6 some of the salts of the carboxymethyloxysuccinic acid will be present in the acid salt form and some in the normal salt form.

An important advantage of the carboxymethyloxysuccinate is its excellent biodegradability characteristics as measured by both standard BOD tests (biochemical oxygen demand for five days) and a modified Soap and Detergent Associations Semicontinuous Activated Sludge Test.

The normal oxydisuccinate builder salts can be prepared in the conventional manner. Thus, the tetrasodium oxydisuccinate may be prepared as follows: An aqueous solution containing 5 grams of oxydisuccinic acid (2,2'- oxydisuccinic acid) in 35 ml. of distilled water is titrated to a pH of 8.6 with a 2 N sodium hydroxide solution. The aqueous solvent is removed under reduced pressure and the residue is tetrasodium oxydisuccinate (tetrasodium 2, 2'-oxydisuccinate). Similarly using carboxymethyloxysuccinic acid and the required amount of sodium hydroxide, the trisodium carboxymethyloxysuccinate can be prepared.

Employing a procedure similar to that given above, the corresponding normal alkali metal, ammonium and substituted ammonium salts of oxydisuccinic 'acid and carboxymethyloxysuccinic acid can be prepared by using a stoichiometric quantity of the appropriate alkaline reactant. The normal mixed salts of oxydisuccinic acid and carboxymethyloxysuccinic acid can be prepared by neutralizing oxydisuccinic acid or carboxymethyloxysuccinic acid respectively with the requisite proportional amounts of basic compounds containing the desired cations.

A preferred method for preparing the carboxymethyloxysuccinate is to react a mixed alkaline earth metal salt such as the calcium salt of maleic acid and glycolic acid in an aqueous alkaline medium. The pH of the medium should be adjusted with an alkaline earth metal reagent such as calcium hydroxide, strontium hydroxide or barium hydroxide.

It has been found that when the reaction is carried out at a pH range of 10.5 to 12.5 as measured initially at room temperature (about 25 C.) yields of about 80-95% carboxymethyloxysuccinate are obtained in a few hours or less. When the reaction is carried out at a preferred pH of about 11.3 to 12.0 as measured initially at room temperature which corresponds to about 9.9 to 10.3 at 100 1?, yields of 90% or better are obtained in less than two ours. i

It has also been found that when using a relatively. insoluble alkaline earth metal hydroxide such as magnesium hydroxide, the initial pH at room temperature of the reaction mixture even with an excess amount of the hydroxide is only about 8 to 9. However, by heating the reaction mixture at reflux temperatures or heating at superatmospheric pressure, satisfactory yields of the product can be obtained.

The mole ratio of glycolic acid to maleic acid used in the reaction is from about 1:1 to about 2:1 and preferably from 1.05:1 to about 1.2:1. The temperature at which the reaction may be carried out is normal'reflux temperature (100-102 C.) or below reflux temperature say, 60 C. However, if the reaction is carried out at temperatures above reflux temperature, 102-200 C., the rate of reaction is increased so that at certain elevated temperatures the reaction may be completed within a matter of minutes.

An interesting intermediate product formed during the reaction of the preferred process is the calcium chelate salt of carboxymethyloxysuccinate corresponding to the following empirical formula: C H O Ca The com pound while represented in the anhydrous form is generally obtained in the hydrated form. This calcium chelate salt corresponds to the calcium of carboxymethyloxysuccinate. The calcium chelate salt and the monocalcium chelate have utility as an animal feed, plant nutrient or any other area requiring calcium. Of course, other alkaline earth metal salts and other polyvalent salts such as zinc, iron, manganese, cobalt and the like could also be formed and used for the same or similar purposes.

While the calcium chelate salt can be isolated directly from the reaction because of its low solubility, the monocalcium chelate, which is highly soluble, must be obtained by either partially decalcifying the calcium chelate salt, e.g., ion exchange resin or, for example, by total decalcification followed by neutralization with one mole of calcium hydroxide and one mole of sodium hydroxide per one mole of carboxymethyloxysuccinic acid. For purposes of convenience, hereinafter the alkaline earth metal or polyvalent metal chelate salts and monoalkaline earth metal or polyvalent chelates of carboxymethyloxysuccinate will be referred to as simply salts of carboxymethyloxysuccinic acid.

While the alkali metal, ammonium and substituted ammonium salts of carboxymethyloxysuccinic acid are very effective builders, they are also effective as boiler scale removers, degreasers, grease cutters and rust and stain removers.

When the oxydisuccinic acid has been prepared in accordance with Example 1 of US. Pat. No. 3,128,287 issued to Chas. Pfizer and Company, Inc., it has been found that a mixture of two diastereoisomeric forms of oxydisuccinic acid will be obtained. The less soluble form has been designated as the d,1-racemate. The more soluble diastereoisomer has been designated as the meso form and is found in the aqueous filtrate after decomposition of the calcium salts with sulfuric acid and removal of the less soluble d,l-racemate. Accordingly, mixtures of meso and d,l-oxydisuccinate can be prepared as well as purified d,l-oxydisuccinic acid and a purified meso-oxydisuccinic acid. Thus these materials may be prepared as follows:

Maleic anhydride, 19.6 g. (0.2 mole), is dissolved in 200 ml. of water and heated to 100 C. for five minutes. Calcium hydroxide, 16.0 g. (0.22 mole), is then added and the mixture stirred and refluxed for four days. The insoluble calcium salts are filtered and dried. The dried product, 22 g. is slurried in water and passed through an Amberlite IR-120 cation exchange column to remove the calcium ions. The eluate is then evaporated to dryness to yield 14.5 g. of crude oxydisuccinic acid.

Examples of the detergent compositions of the invention are set forth below as illustrative but not limited to such compositions.

The detergent formulations set forth below are prepared by blending together the recited components and are then tested for detergency or cleansing ability in the Terg-O-Tometer Test wherein the washing conditions areas follows (unless otherwise indicated): Dacron- 35% cotton VCD (vacuum cleanerv dust) cloth; 120 F.;

Automatic Color Difference Meter, Model AC-3 180 ppm. water (2/1 Ca++/Mg++); 0.15% concentration of the total formulation in the washing solution; pH 9.5. (The pH of the washing solutions given herein was adjusted, where necessary, by the addition of caustic (NaOH) or sulfuric acid thereto.)

The average detergency units (DU) of the formulations'is the-final reflectance of the washed cloth minus the initial reflectance of the soiled cloth (the average of two runs), the reflectance being measured with a Gardner The following abbreviations have been used in the tables and examples: LAS is an anionic surfactant which is sodium linear secondary alkyl (C -C benzene sulfonate'yNeodol 45-11 is a nonionic surfactant which is an adduct of a modified 0x0 typeC C alcohol with salt derived from two moles of the monocalci urnfichelatel an average of 11 moles of ethylene oxide; 014-01 HAMT 15 an ampholytic surfactant which is sodium hydroxyalkyl (C -C N-methyltaurate; (DCH) sulfobetaine is a EXAMPLES 12-14 zwitterionic surfactant which is cocodimethylsulfopropyl DETERGENOY BUILDING PROPERTIES OF TRISODIUM betaine; NaOD 1s tetrasodiurn oxydisuccinate; STPl 1s CARBOXYMETHYLOXYSUOCINATE WITH SODIUM pentasodium tripolyphosphate; TKPP 1s tetrapotasslum SULFATE PY P P i NTA i5 trisodium nitrilotliacetate; RU 5 [Washing conditions: Terg-O-Tometer; Daeronlcotton VCD cloth; 120 silicate is a sodium silicate having a SiO :Na O ratio of i gf (MOW/Mg) Water; 01% imminent) ctmcentmimi 2.4:1; DU is detergency units; and bal. is balance. p

The eifectiveness of the carboxymethyloxysuccinate 11 rE mp e salts as detergent builders is exemplified in Examples 1-18 Components 12 1s 14 and 33-36 LAS, percent 1s 1s 18 More specifically, Examples 1-10 show the use of tri- Trisodium carboxymethyloxysuccinate,

sodium carboxymethyloxysuccinate as a detergent builder Percent STPP,percent 40 with various surfactants. Example 11 describes the use Sodiumsulfate,percent of trisodium carboxymethyloxysuccinate in a machine vRvggmcatemlidsrpement dishwashing composition. Examples l2-14 illustrate the Detergency(DU's) enhancement of the detergent building properties of tri- Pemnteffimemy(12VS-14and13VS'14)" 96 sodium carboxymethyloxysuccinate in the presence of added sodium sulfate. Examples 33-36 show the enhance- EXAMPLES 15 16 ment of detergent building properties of carboxymethyloxysuccinate by use of higher levels of surfactant. preferrgd of tilsidlum In all cases except for Example 11 the detergency tests car oxyme y oxysuccma 6 were carried out as set forth in examples above and as Maleie anhydride mole; 8-) is dissolved in modified in the description of the washing conditions Water (100 ml.) at room temperature and stirred for stated at the beginning of the examples, In the case of 10-15 minutes t0 convert it to the acid. Glycolic acid Example 11, the detergency properties were established mole; g-) is then added and dissolved h by Washing artificially soiled glasses and dishes in a Stirring- Calcium hYdIOXide, mole; 27 Sllfli' standard home dishwashing machine and comparing the cient to attain a pH of 11.4 as measured initially at 25 results with those obtained with a standard sodium triis next a ded while stirring the reaction mixture polyphosphate-built formulation. The artificial soil is a g Y- The lIliXfllre iS t d t r flux and maintain d mixture of milk, vegetable residues, lipstick, gravy, starch, at reflux for two hours while stirring vigorously. After eggs and lard. cooling to C., finely ground sodium carbonate (0.4

Examples 15-32 Sh th preferred th d f th mole; 42.4 g.) is added and stirring continued for fifteen preparation of carboxymethyloxysuccinic acid and the salts minutes at T m u iS then cooled to room thereof. temperature and the suspended CaCO filtered off and EXAMPLES l10 TRISODIUM CARBOXYMETHYLOXYSUCCINATE AS A DETERGENT BUILDER [Washing conditions: Terg-O-Tometer; Dacron/cotton VCD cloth; 120 F.; 180 p.p.m. (2:1 Ca++/Mg++) water; 0.20% concentration of total formulation for Examples 1 and 2; 0.25%. Concentration for Examples 3 to 10; pH=10.0]

Formulation for Example Component 1 2 3 4 5 6 7 8 9 10 Trisodium salt of carboxyrnethyloxysuccinic acid,

CrPCm H percen Suliobetaine DCH, percent Sodium 0 43 9 a-olefin sulfonate, percent- Water, percent Average detergency (D U's) Percent efficiency vs. control formulation Balance Balance Balance Balance Balance Balance Balnace Balance Balance Balance 23.0 24.3 21.690 24.1 19.7 24.1 23.5 24.3 22.6 24.9

1 I.e., 1 vs. 2; 3 vs. 4; 5 vs. 6; 7 vs. 8; and 9 vs. 10.

EXAMPLE 11 washed with water. The filtrate (including the washings) I contains the product, trisodium carboxymethyloxysuccin- A machine dishwashing composition is prepared w t ate, in yields of about 95% as determined by NMR the following materials: 0 analysis.

I Percent The NMR analysis, which can be run before or after TriSOdillm Salt of eafboxymeihyloxysucclmc acld treatment with the sodium carbonate, involves taking a Chlorinated trisodium phosphate 25 ml. sample of the reaction mixture and treating it with N silicate So sioz/Nazo a cation exchange resin. After filtering and washing the RU silicate solids 5 resin with water, the combined filtrate and washings are Pl L62 nonionic Surfactant Sold by y evaporated to a residue in vacuo. An NMR analysis of dOtte Chemical Corporation which is all ethylene the residue in D 0 is then performed. The percent coneflide Condensate of a P Y YP PY g y version of maleic anhydride to carboxymethyloxysuccinate Sodium sulfate equals 100x [ratio of the area of the chemical shift for Water carboxymethyloxysuccinic acid at 2.6-3.35 (2H) to the sum of the areas for the chemical shifts for unreacted The above formula has acceptable dishwashing propmaleie acid at approximately illmarie acid erties which are similar to those of the same formula con- (which y form during reaction) at app oximat ly 6-86 taining sodium tripolyphosphate in place of the trisodium and ym t yl xysu inic acid at .63-36 carboxymethyloxysuccinate. (2H)].

The procedure of Example 15 is repeated except the mixture is refluxed for thirty minutes as opposed to two hours and the pH of the solution obtained after filtering ofi the CaCO is adjusted to 8.6 with 10% sulfuric acid. Yields of about 93% are obtained.

EXAMPLE 17 The reaction mixture from Example 15 is cooled and before treatment with sodium carbonate, the intermediate calcium chelate salt is isolated by filtration (percent Ca calculated for C H O Ca -H O, 22.5; found, 22.9). The product is then decalcified by treatment of an aqueous slurry of the product with a cation-exchange resin followed by filtration and evaporation of the filtrate. The residue of carboxymethyloxysuccinic acid solidifies on cooling to a crystalline mass, M.P. 112-113 C. The acid is then converted into a salt by partial or complete neutralization with sodium hydroxide to form mono-, dior trisodium carboxymethyloxysuccinate.

EXAMPLES 18-22 In place of the calcium hydroxide of Example 15, the divalent metal hydroxides Mg(OH) Sr(OH)2, Ba(OH) and Zn(OH) are used.

Using Mg(OH) in the reaction of Example 15 with 200 ml. of water in place of 100 ml. of water and at an initial pH of 9 (measured at room temperature) gives a 79% conversion of maleic anhydride into product after 17 hours refluxing at 100 C.

Similarly with Sr(OH) at initial pH of 11.5 (measured at room temperature), the conversion is 88% in four hours at 100 C. With Ba(OH) at initial pH of 10-11, the conversion is 54% after ten hours at 100 C. With Zn(OH) and at an initial pH of 8, a 47% conversion is obtained after nine hours at 100 C. With Ca(OH) at initial pH of 11, the conversion is 91.5% in less than minutes at 150 C. The speed of the reaction with Ca(OH) makes it feasible for the process to be run continuously.

EXAMPLES 23-28 The procedure of Example 15 is repeated except that 200 ml. of water is used and the amount of calcium hydroxide used is sufiicient to obtain the following pHs as measured initially at room temperature.

Percent conversion of maleic anhydride to trisodium earboxymethyloxysuccinate after two hours reuxing EXAMPLE 29 The procedure of Example 15 is repeated except the 200 ml. of Water is used and 27.5 g. of zinc oxide (.338 mole) is used in place of 27.0 g. of calcium hydroxide to adjust the pH to about 8.0. The percent conversion of maleic anhydride to trisodium carboxymethyloxysuccinate after two hours refluxing is 41% as determined NMR analysis.

EXAMPLES 30-31 The procedure of Example 15 is repeated except that the reaction mixture is heated at 60 C. for two hours. The conversion of maleic anhydride to carboxymethyloxysuccinate is -88 EXAMPLE 32 The procedure of Example 15 is repeated except the pH is adjusted to 12.0 and the reaction mixture is refluxed for 15 minutes. The conversion of maleic acid to carboxymethyloxysuccinate is 90% based on NMR analysis.

At high pH and continued refluxing, the carboxymethyloxysuccinate product formed may undergo a retro Michael reaction giving rise to the fumarate salt.

Referring to Examples 33-36, it has been determined that by increasing the level of the surfactants used in the detergent formulations and particularly the anionic and zwitterionic actives, the detergency of the formulations are enhanced. It has also been found that LAS and alphaolefin sulfonate salts are very eifective for this purpose.

Examples 33-36 clearly demonstrate that when the levels of LAS are increased, the detergency of the formulation is enhanced significantly when compared to a standard LAS/tripolyphosphate formulation. When using other actives, similar efiects are observed.

EXAMPLES 33-36 TRISODIUM CARBOXYMETHYLOXYSUCCINATE AS A DETERGENT BUILDER WITH VARIOUS LEVELS OF'AN ANIONIC SURFACIANT [Washing conditions: Terg-O-Tometer; Dacron/cotton VGD cloth; F; p.p.m. (2:1 Ca /Mg water; 0.2% concentration of total formulation; pH=10.0]

It is intended to cover all changes and modifications of the preferred embodiments of the invention, herein chosen for the purpose of illustration, which do not constitute departures form the spirit and scope of the invention.

What is claimed is:

1. A detergent composition comprising (1) a watersoluble organic detergent compound selected from the group consisting of anionic, nonionic, zwitterionic and ampholytic detergent compounds and (2) a builder salt having the general formula: v

H MOOC--H Iii MOOC- H H-C-COOM wherein M is selected from the group consisting of alkali metal, ammonium and substituted ammonium cations and combinations thereof, the weight ratio of said builder salt to detergent compound ranging from about 1:20 to 50: 1.

2. The detergent composition as defined in claim 1 wherein said detergent composition contains sodium carbonate.

3. The detergent composition as defined in claim 1 wherein the organic detergent is alpha olefin sulfonate having a chain length from C to C 4. The detergent composition-as defined by claim 1 wherein the weight ratio of the builder salt to detergen compound ranges from about 1:20 to about 20:1. 7

5. The detergent composition as defined by claim 1 wherein the carboxymethyloxysuccinate is trisodium carboxymethyloxysuccinate.

References Cited UNITED STATES PATENTS 3,293,176 12/1966 White 210-58 2,264,103 11/1941 Tucker 210-23 10 2,311,008 2/1943 Tucker 210 23 3,332,880 7/1967 Kessieretal 252-536X MAYER WEINBLATT, Primary Examiner V vs. c1. X.R.

o V UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT N0. 3,692,685 DATED September 19, 1972 Q INVENTOR(S) Lamberti, et a1.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

0 Col. 2, line 13: delete the phrase "R is H or -CH COOM and".

Col. 2, line 19: delete the "comma" after the word "triammonium" 0 Col. 2, line 43: add a comma after the word "oxydisuccinate".

Col. 5, line 9: change "l-l8" to l-l4 Col. 7, line 61: change "the" (last word in line) to O that Col. 7, line 66: insert the word by between "determine" and "NMR" A Col. 8, line 37: In Table, Example 36: change "81" to Signed and Scaled this Twenty-fifth D3) 0f September 1979 [SEAL] Attest:

LUTRELLE F. PARKER J Attesting Ojficer Acting Commissioner of Patents and Trademarks 

